Is A-Tanazir Quandrix legal in Standard, Modern, and Commander?

A-Tanazir Quandrix is legal in: Historic.

A-Tanazir Quandrix

Q: What type of card is A-Tanazir Quandrix?

A-Tanazir Quandrix is a Legendary Creature — Elder Dragon. Its oracle text reads: "Flying, trample When Tanazir Quandrix enters, double the number of +1/+1 counters on target creature you control. Whenever Tanazir Quandrix attacks, you may have the base power and toughness of other creatures you control become equal to Tanazir Quandrix's power and toughness until end of turn. Power/Toughness: 5/5"

Legendary Creature — Elder Dragon

Flying, trample

When Tanazir Quandrix enters, double the number of +1/+1 counters on target creature you control.

Whenever Tanazir Quandrix attacks, you may have the base power and toughness of other creatures you control become equal to Tanazir Quandrix's power and toughness until end of turn.

Power/Toughness: 5/5

Set Strixhaven: School of Mages

Rarity Mythic Rare

Mana Value 5

Artist Raymond Swanland

Collector # A-240

Scryfall